Summer’s a little early in the west

THIS year’s autumn was the driest in years, according to rainfall figures which also showed significant differences around the western suburbs.

Melton’s rainfall total dropped from 153.4mm in autumn last year to 70.2mm this year. Merrimu Reservoir, which provides drinking water to Melton and Bacchus Marsh, had 73mm of rainfall in autumn – down from 110.8mm last year.

Data from Melbourne Water’s network of rain gauges across Melbourne’s west shows autumn was drier than average at almost all suburban locations. Across Melbourne, water storages at the start of autumn were 75.8 per cent full; they ended the season 70 per cent full. 

Melbourne Water spokesman Nick McGay said the 5.8 per cent fall represented a net loss from the storages of 106 billion litres, compared to the long-term average loss of 4.3 per cent in autumn.

Despite the decline, Melbourne’s storages finished the season at their highest end-of-autumn level since 1997, and 5 per cent higher than the same time last year. 

“With the catchments already dry from a long, hot summer, the resulting 33 billion litres of streamflow into the reservoirs was 37 per cent below the long-term average,” Mr McGay said. 

“It was a similar story in the four major catchments [Maroondah, O’Shannassy, Upper Yarra and Thomson] that harvest most of Melbourne’s water.”

Mr McGay said Melbourne’s total autumn water use for home, business and industry averaged 1121 million litres a day, 13 per cent higher than at the same time last year. 

June rainfall was 44 per cent above average and added 0.8 per cent to storage across the state, bringing the total level to 70.8 per cent.